The overall aim of this project is to understand the mechanism by which myosin molecules self-assemble to form myosin filaments. To achieve this aim recombinant DNA technology will be used. Starting with fragments of the myosin molecule which have characteristic assembly properties we will define the human embryonic myosin heavy chain (HEMHC) gene segment corresponding to the fragment. Starting with synthetic oligonucleotides flanking the region of interest we will amplify the gene segment using the polymerase chain reaction. This segment will be expressed in E. coli to verify that it retains the assembly characteristics. The gene segment will then be modified by shortening or elongating to express different size fragments. In this way the changes in the assembly characteristics related to different portions of the myosin molecule will be defined. From the amino acid sequence, characteristic properties of the sequence will be related to the assembly characteristics. Using this information a mechanism for the assembly of myosin should evolve.